What kind of failure cases need to replace the bearing

Bearing in the factory before using, its service life has been tested, but as a result of using environment or method is different, in fact bearing's life and the actual. Some bearing were problems have not reached during the life, that had to change ahead of time, authors introduce you today which need to replace the bearing fault cases. For these bearing failure frequency calculation, have special mathematical formula, but in the practical work of calculation more troublesome, convenient method is to use special software to get, as long as the input bearing model and the information such as the manufacturer, they can get the corresponding all kinds of bearing failure frequency. Press as a whole, failure frequency aura can use the following analysis: rolling bearing failure frequency of four stages: the first stage, the bearing start malfunctioning infancy, when temperature is normal, normal noise and vibration velocity and total spectrum is normal, but the peak signs, total energy and spectrum reflect the beginning of the bearing fault. When the real bearing failure frequency in ultrasonic period of approximately 20 - 60 KHZ range. Increases slightly in the second stage, the temperature is normal, noise, vibration velocity increases slightly, total vibration frequency change is not obvious, but the peak energy has a big increase, spectrum is also more prominent. At this time of the bearing fault frequency in about 500 hz - 2 KHZ range. The third stage, the temperature is a little higher, but heard the noise and vibration velocity has a large amount of increase, and the vibration velocity spectrum is clearly visible on the bearing fault frequency and its harmonics and sideband, the other on the vibration velocity spectrum noise significantly elevated horizon, rush total energy compared to the second stage become bigger, the spectrum is also more prominent. At this time of the bearing fault frequency in about 0 1 KHZ range. Suggest that late in the third stage to replace its bearing, so at this time should have appear to the naked eye can see the rolling bearing fault characteristics such as wear and tear. The fourth stage, the temperature rise obviously, noise intensity change obviously, the total amount of vibration velocity and vibration displacement are increased, the vibration velocity spectrum on the bearing fault frequency began to disappear, broadband high frequency noise is more random horizon; Total peak energy increases rapidly, and some unstable changes may occur. Never let bearing in the fourth stage of fault development, otherwise will may be catastrophic damage. According to the results, in general the whole service life of rolling bearings is then put into use from bearing installation plan, before it's & amp; gt; 80% life period, bearing is all normal. And the corresponding development of rolling bearings' faults, and its residual life in the first stage is 10% ~ & amp; gt; L10, 20% to 5% in the second stage 10% in the third stage is 1% ~ 5% L10, L10, L10 phase 4 is approximately 1 h or 1%. Therefore, in the practical work is faced with the problem of bearing, considering the development of the bearing fault in the fourth phase is harmful to the unpredictable sudden, suggest that late in the third stage to replace bearings, both to avoid failure of expansion and more serious accidents, and to try to ensure the service life of rolling bearing, and according to the bearing on has also appear to the naked eye can see the wear and tear, damage to the parts, such as rolling bearing fault characteristics, more persuasive. As to bearing fault in the late development of the third phase identification, requires the characteristics on the basis of the above theory combined with the actual temperature, noise, velocity spectrum and energy spectrum peak, peak velocity and the amount of energy trends and practical experience to be considered.